1. Field
The following description relates to an apparatus and a method for reducing crosstalk induced due to chrominance information included in a lightness signal and lightness information included in a chrominance signal.
2. Description of the Related Art
A lightness signal indicates lightness of an achromatic component. A chrominance signal indicates relative amounts of a yellow-blue chromatic component and a red-green chromatic component. The lightness signal includes chrominance information while the chrominance signal includes lightness information. Therefore, crosstalk exists between the chrominance signal and the lightness signal. The crosstalk is caused by the following reasons.
For one reason, a lightness mixture ratio of primary red green blue (RGB) colors necessary for creating the color white having a specific color temperature is to be applied to a linear RGB signal. However, since the lightness mixture ratio is applied to a nonlinear RGB signal and the lightness signal includes the nonlinear RGB signals, the crosstalk is caused between the chrominance signal and the lightness signal.
For another reason, the chrominance signal is generated using a difference between the lightness signal includes the nonlinear RGB signals and the nonlinear RGB signal.
In other words, two colors having the same lightness may have different lightness signals. Such inconsistency between the lightness and an actual amount of the lightness signals is color-dependent. Therefore, when an image including the lightness signal and the chrominance signal is sub-sampled, the sub-sampled image may be deteriorated.
Accordingly, there is a demand for technology for reducing the crosstalk between the lightness signal and the chrominance signal.